Halfmoon Lake   Be the first to submit input for Halfmoon Lake. If you have info on Halfmoon Lake, Washington County, Illinois please submit it here to improve this web site.          These outdoors activities are available near Halfmoon Lake.   Hotels Near Halfmoon Lake: Super 8 Okawville, Okawville, 6 miles away Timmermann House Bed & Breakfa, Aviston, 8 miles away La Quinta Inn & Suites O'Fallon/Mascoutah, Mascoutah, 14 miles away Holiday Inn Express HIGHLAND, Highland, 16 miles away Best Western U. S. Inn, Nashville, 18 miles away   Ski Areas Near Halfmoon Lake: Hidden Valley, Missouri, 71 miles away       250 foot drop, 6 lifts, 9 runs